The Metric System

• The scientific system of measurement

• The International System of Units (SI)

• Based on the number 10 and multiples of 10

Length

• Distance between two points• Meter (m) = basic unit of length

= 39.4 inches• Metric rulers and meter sticks

used to measure

Meter stick -- 1 meter or 100 cm or 1000 mm long

Metric ruler -- 30 cm or 300 mm long

Volume

• The amount of space an object takes up

• Liter = the basic unit of volume (L)

• Cubic Centimeter (cc or cm3) – used to measure the volume of solids

1 ml = 1 cc = 1 cm3

1000 ml = 1 L

• Liquid: Measured with graduated cylinder

Meniscus -- the curved surface of a liquid in a graduated cylinder. Read the bottom of the meniscus.

• Irregular solid: Measure out some water

in the cylinder. This is volume 1. Drop the solid into the liquid causing the water level to go up. This is volume 2. Subtract volume 1 from volume 2 to get the volume of the solid.

• Solid: volume = length x width x

height

Mass

• The measure of the amount of matter in an object

• Kilogram (kg) = basic unit of mass

• Measured with balance

Density

• The mass per unit volume of a substance

• Density = MassVolume

• Density of water = 1 g/mL

• Objects with density less than 1 g/mL float on water.

• Objects with density more than 1 g/mL sink in water.

Temperature • Celsius scale is usual

measurement but SI unit is Kelvin• The Kelvin temperature can be

found by adding 273 to the Celsius reading

Water freezes at 0oC Water boils at 100oCBody temperature = 37oCRoom Temperature = 21oC

• Temperature is measured with a thermometer

Time

• The interval between two events• Measured in seconds